<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>Insert title here</title>
</head>

<body>
    a.jsp<br/>
    全域查找：${msg}<br/>
    requestScope:${requestScope.msg}
    sessionScope:${sessionScope.msg}<br/>
    applicationScope:${applicationScope.msg}
</body>